InfoPath Dev

I know this is probablly a simple fix. I have a repeated section where user will add item details. the row has a button that is enabled once the section is complete. they click the button and it adds a row and field values to another repeating section on another view. On this view they can add cost and rates. I have successfully accomplished this, but the rates are being added in descending order. When I clone the table and set the value it is added to the first row. I am not sure why this is.  Here is my code, can someone see what I am missing?

public void CreateRates_Clicked(object sender, ClickedEventArgs e)
        {
            XPathNavigator root = MainDataSource.CreateNavigator();
            XPathNavigator DOM = e.Source.CreateNavigator();
            XPathNavigator details = root.SelectSingleNode("/my:myFields/my:myRateDetails/my:CmdtyAssignmentGrp", NamespaceManager);
            XPathNavigator repTable = details.SelectSingleNode("my:CommodityAssignment[last()]", NamespaceManager);
            
            XPathNodeIterator rows = root.Select("/my:myFields/my:myRateDetails/my:CmdtyAssignmentGrp/my:CommodityAssignment", NamespaceManager);

            XPathNavigator rCount = root.SelectSingleNode("/my:myFields/my:myRateDetails/my:CmdtyAssignmentGrp/my:CommodityAssignment/my:rCount", NamespaceManager);

            XPathNavigator CmdtyRate = details.SelectSingleNode("/my:myFields/my:myRateDetails/my:CmdtyAssignmentGrp/my:CommodityAssignment/my:CmdtyRate", NamespaceManager);

            string LINum = DOM.SelectSingleNode("my:LINum", NamespaceManager).Value;
            string RateAssignmentDS = DOM.SelectSingleNode("my:RateAssignmentDS", NamespaceManager).Value;

            XPathNavigator node;

                node = repTable.Clone();
                details.AppendChild(node);

                node.SelectSingleNode("my:CmdtyRow", NamespaceManager).SetValue(LINum);
                node.SelectSingleNode("my:CmdtyRate", NamespaceManager).SetValue(RateAssignmentDS);
                //node.SelectSingleNode("my:FieldC", NamespaceManager).SetValue("FieldC - Row " + i.ToString());

                //details.AppendChild(node);

           
         //delete first blank row
            while (rows.MoveNext())
            {
                string CurrentRow = rows.Current.SelectSingleNode("my:CmdtyRate", NamespaceManager).Value;
                if (CurrentRow == null || CurrentRow == "")
                {
                    rows.Current.DeleteSelf();
                    break;
                }

            }
        }

never mind, i figured it out. I change appendchild to insertafter and used MoveToNext before setting field values. Work perfectly.